Distributed Inter-Domain Multi-Constrained Routing

With recent advances in the communication technologies (e.g. LTE and 5G), we are witnessing a deployment of a wide range of network real-time applications like telemedicine, VoIP, remote control applications for drones and cars, e-health, etc. These applications often require the verification or optimization of various quality of service (QoS) parameters, such as the delay, the error rate, the failure probability, the energy, etc. Though several algorithms have been developed to provide QoS in intra-domain networks, there are few works which are devoted to the inter-domain multi-constrained (or multi-criteria) routing. This is essentially due to the difficulty to deal with the two inter-domain major issues which are: scalability and confidentiality. In this paper, we propose an efficient and distributed multi-constrained routing algorithm for multi-operator or inter-domain networks. Our algorithm guarantees the determination of paths ε-close to the optimums. It is fully polynomial time and it respects the inter-domain constraints. Besides, it reduces the message exchanges by aggregating the path weights

Hybrid Scale-Based Approximation Algorithm for QoS Routing

International audienceWith the widespread use %and the increase of the number of network applications (VoIP, IPTV, etc.) which are sensitive to multiple QoS parameters (delay, jitter, error rate, financial cost, etc.), multi-constrained QoS routing becomes increasingly desired. Such routing is proved to be NP-hard when the number of additive metrics to be optimized is equal or greater than two. Thus, multiple fully polynomial approximation algorithms have emerged. These algorithms are essentially based on two scales: linear and logarithmic. In this paper, we prove that both the two scales could be inefficient for QoS path pre-computations and then propose a new algorithm that employs a hybrid scale to enhance path computations. As we proved it formally and by simulations, our algorithm guarantees reduced time responses for the pre-computed QoS paths without deteriorating their approximation quality

Resource Sharing Strategies: Which Sharing to Better Protect Primary Shortest Paths?

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Resource Saving: Which Resource Sharing Strategy to Protect Primary Shortest Paths?

International audienceTwo strategies of resource sharing are proposed in literature to provide protection while saving resources: (1) restrained sharing which applies the resource sharing to the backup paths only and (2) global sharing which extends the resource sharing to the primary and backup paths.In this paper, we compared the two strategies of resource sharing when the primary paths correspond to the shortest ones according to a strictly positive and static metric. Even when the amount of resources that can be shared between the primary and the backup paths is unbounded, we proved that the maximum number of backup paths is still bounded. Besides, our simulations showed that the resource sharing between the primary and backup paths has very slight impact on the backup path rejection, i.e. the two strategies of resource sharing have very close performances

A Cloud-Oriented Algorithm for Virtual Network Embedding over Multi-Domain

The rapid deployment of cloud computing service needs a robust and efficient virtualization layer between the application and the physical hardware. Network Virtualization, which allows the co-existence of various logical networks on shared physical infrastructure, is an important technique to face this challenge. The optimal mapping of virtual resource to physical resource is a major issue in network virtualization. This problem, called virtual network embedding (VNE), has been well explored in the context of one physical domain, which is in practice operated by a single infrastructure provider (InP). However, with the rapid growing of cloud computing services, quite a number of VNs have to be established across multi-domain. For multi-domain VNE, infrastructure providers can no longer just solve their own single domain VNE problem, but have to cooperate to build the whole VN. Therefore, new challenge arises for the multi-domain VNE, compared to traditional single domain VNE. The existing investigations on this problem mainly focus on decomposing a VN to sub VN for each domain, but few attention has been paid to the joint relation between intra-domain and inter-domain (peering) links. In this paper, we propose a multi-domain link mapping framework which combines the intra and peering link mapping so as to optimize the overall resource utilization. Our approach is easy to be deployed since it is based on current Internet architecture. Evaluation shows that our approach, brings improvements related to existing methods

Genetic algorithm based model for capacitated network design problem

Efficient design of networks topologies is challenging, especially with the arrival of the virtualization in these last years. In this paper, we deal with the Capacitated Network Design Problem (CNDP) with modular link capacities to design minimum cost network while satisfying the flow demands. We propose a two levels Genetic Algorithm (GA) based model that can deal with several variations of CNDP. Our proposition defines a new encoding scheme to treat the modular case. Extensive simulation results on Atlanta, France and Germany network instances show that the proposed algorithm is much more efficient than the Iterative Local Search algorithm

Survivable services oriented protection level-aware virtual network embedding

International audienceNetwork virtualization permits the creation of several logical networks (virtual networks) on one shared physical network referred as the substrate network. To protect a network against single substrate link failures, fast local reroute is preferred. With the reservation of backup resources, the flows are switched quickly from primary to backup paths upon substrate link failure to ensure service continuity.Due to the difficulty of primary and backup mappings, most of works in the literature separates the mapping of primary virtual network from the setting of backup paths. Although this approach optimizes primary resources, it can lead to inefficient protection since the existence of backup paths depends on the selected primary paths. In this paper, we propose a framework for protection-level-aware virtual network embedding which minimizes the risks of unrecoverable failures. With our propositions, the primary paths are selected among those which can be fully protected, if there is no such path, then we take the least vulnerable links in order to minimize the failure probability. For primary mapping, we propose a flexible on-line backup verification-based heuristic and a fast backup pre-verification-based heuristic. With the first heuristic, the backup path feasibility is verified on-line for each potential primary link, whereas we pre-compute for each substrate link the optimized set of backup tunnels all the backup paths in advance are deduced with the second heuristic. Simulations show that our propositions significantly reduce the substrate link failure impact on virtual networks, at the price of a slight decrease of the primary acceptance ratio

Protection remontante des communications multicast

9 pagesLa protection des communications multicast devient de plus en plus importante avec l'avènement et la multiplication des applications multicast temps réel telles que la vidéo à la demande, la vidéo conférence, le jeu en réseau, etc. Ces applications sont sensibles aux ruptures des communications et ont besoin de tourner sur des réseaux robustes et permettant une récupération rapide des pannes. Pour ce faire, différentes techniques de protection multicast proactive ont été développées. Ces techniques permettent de maintenir les communications (ou de diminuer des temps de leur rupture) grâce au pré-calcul et plus souvent à la pré-configuration de chemins de secours utilisables après la détection d'une panne. Dans cet article, nous présenterons la technique de protection remontante qui permet de protéger efficacement les communications multicast par l'utilisation d'une forêt de secours. Cette dernière est construite par l'interconnexion des noeuds de l'arbre primaire en commençant par les noeuds les plus en bas de l'arbre primaire (les noeuds feuilles d'abord) et en remontant jusqu'au noeud source. Les simulations montrent que cette technique de protection remontante présente un taux de protection légèrement inférieur au taux idéal et très supérieur à celui correspondant à la technique de protection par forêt duale

Multi-Domain Virtual Network Embedding with Coordinated Link Mapping

Network Virtualization, which allows the co-existence of various logical networks on shared physical infrastructure, has become popular in recent years. The optimal mapping of virtual resource to physical resource is a major issue in network virtualization. This problem, called virtual network embedding (VNE), has been well explored in the context of one physical domain, which is in practice operated by a single infrastructure provider (InP). However, the needs of virtual network (VN) is rapidly growing, and quite a number of VNs have to be established across multi-domain. For multi-domain VNE, infrastructure providers can no longer just solve their own single domain VNE problem, but have to cooperate to build the whole VN. Therefore, new challenge arises for the multi-domain VNE, compared to traditional single domain VNE. The existing investigations on this problem mainly focus on decomposing a VN to sub VN for each domain, but little attention has been paid to the joint relation between intra-domain and inter-domain (peering) links. In this paper, we propose a multi-domain link mapping method which combines the intra and peering link mapping so as to optimize the overall resource utilization. Our approach is easy to be deployed since it is based on current Internet architecture. Evaluation shows that our approach brings improvements related to existing methods

A failure avoidance oriented approach for virtual network reliability enhancement

International audienceNetwork virtualization allows the co-existing of logical networks (virtual networks) on physical network (substrate networks). Virtual Network (VN) reliability is a critical problem for end-users and service providers. It aims to ensure service continuity even upon failure. As more and more VNs are created over substrate networks (SN), the failure of a single SN component may lead to the failure of many VNs. Thus, the VN reliability issue is becoming more and more critical. VN reliability can be enhanced in two ways: (1) by failure recovery (post-failure) with protection and/or restoration methods; (2) by failure avoidance with the selection of most reliable components at the network topology setting phase. Traditional virtual network embedding (VNE) methods have mainly focused on bandwidth optimization. In this paper, we focus on the reliability issue. We propose VNE methods which take into account the failure probability of SN components with a failure-avoidance approach, in order to minimize the VN failure probability. Our heuristics are based on the use of Steiner Minimal Tree (SMT). Simulations results confirm that our heuristics provide better reliability against traditional VNE with bandwidth as sole target, and, in case of failure of a SN component, reduce the number of affected VNs